The purpose of this application is to demonstrate the capability of The Ohio State University AIDS Clinical Trials Unit's virology laboratory to function as one of the core Virology Laboratories for the ACTU network. This ACTG laboratory will perform the protocol virologic monitoring as mandated by the ACTG protocols and Virology Core Committee. These include HIV antigen testing, HIV cultures and the measurement and evaluation of other viral markers as diagnostic methods evolve. Participation in quality assurance programs will standardize and validate assay results. Prior experience in the performance of a large number of these assays and the maintenance of a high level of proficiency and quality control for the last three years attests to the capability of this laboratory to perform this work. The OSU ACTU virology laboratory was/is not primarily organized as a basic research laboratory doing experimental studies ut as a clinical laboratory developing standardized assays. This concept is most important in performing the protocol mandated virologic assays where the goal is providing consistently accurate results using a consensus assay on a large number of specimens. Laboratory certifications from a variety of organizations attests to achieving this goal. Nevertheless the laboratory still has performed well in the application and development of virologic assays in the clinical setting and currently participates in the on-going evaluation of new quantitative virologic culture techniques. In addition, the virology facilities were recently constructed and were built with an expansion in function expected. Thus, both space and equipment are ample to safely handle the expected increase in specimen load.